1. Field
Embodiments relate to a battery pack.
2. Description of the Related Art
Secondary batteries, i.e., rechargeable batteries, may be charged and discharged repeatedly, unlike primary batteries. Secondary batteries are widely used in electronic devices, e.g., cellular phones, notebook computers, and camcorders. Recently, secondary batteries have been used as batteries for, e.g., electric bicycles, electric scooters, electric cars, and hybrid electric vehicles (HEV).
A secondary battery may include an electrode assembly and an electrolyte. The electrode assembly may include a positive electrode plate, a negative electrode plate, and a separator. The electrolyte may include lithium ions. The electrode assembly and the electrolyte may be received in a case to form a unit battery cell of the secondary battery.
When unit battery cells are stacked in horizontal or vertical direction, a battery module is formed. In addition, a plurality of battery modules may be stacked in the horizontal or vertical direction to form a battery pack.
A battery pack may be used in environments where there are a lot of vibrations. In particular, when a battery pack is used in an electric bicycle, an electric scooter, an electric car, or an HEV, the battery pack may be greatly affected by vibrations. When a secondary battery is exposed to vibrations, performance thereof may degrade or the lifespan of the secondary battery may be reduced due to being physically damaged.
In particular, when battery modules are fixedly coupled to an electric car, for example, each of the battery modules may receive vibrations from the electric car.
Accordingly, the battery modules may be coupled to each other using coupling members having elasticity. However, when elastic coefficients of the coupling members coupled to the battery modules are similar to each other, the battery modules may have similar natural resonant frequencies. Thus, the battery modules may be simultaneously resonated due to vibrations at a certain frequency.